In the diagram representing the development of shi-nä there is an elephant. The elephant symbolizes the meditator's mind. Once an elephant is tamed, he never refuses to obey his master and he becomes capable of many kinds of work. The same applies to the mind. Furthermore, a wild and untamed elephant is dangerous, often causing terrible destruction. Just so, the untamed mind can cause any of the sufferings of the six realms.
At the bottom of the diagram depicting the development of concentration the elephant is totally black. This is because at the primary stage of the development of shi-nä mental torpor pervades the mind.
In front of the elephant is a monkey representing mental agitation. A monkey cannot keep still for a moment but is always chattering and fiddling with something, being attracted to everything.
The monkey is leading the elephant. At this stage of practice mental agitation leads the mind everywhere.
Behind the elephant trails the meditator, who is trying to gain control of the mind. In one hand he holds a rope, symbolic of mindfulness, and in the other he holds a hook, symbolic of alertness.
At this level the meditator has no control whatsoever over his mind. The elephant follows the monkey without paying the slightest attention to the meditator. In the second stage the meditator has almost caught up with the elephant.
In the third stage the meditator throws the rope over the elephant's neck. The elephant looks back, symbolizing that here the mind can be somewhat restrained by the power of mindfulness. At this stage a rabbit appears on the elephant's back. This is the rabbit of subtle mental torpor, which previously was too fine to be recognized but which now is obvious to the meditator.
In these early stages we have to apply the force of mindfulness more than the force of mental attentive application for agitation must be eliminated before torpor can be dealt with.
In the fourth stage the elephant is far more obedient. Only rarely does he have to be given the rope of mindfulness.
In the fifth stage the monkey follows behind the elephant, who submissively follows the rope and hook of the meditator. Mental agitation no longer heavily disturbs the mind.
In the sixth stage the elephant and monkey both follow meekly behind the meditator. The meditator no longer needs even to look back at them. He no longer has to focus his attention in order to control the mind. The rabbit has now disappeared.
In the seventh stage the elephant is left to follow of its own accord. The meditator does not have to give it either the rope of mindfulness or the hook of attentive application. The monkey of agitation has completely left the scene. Agitation and torpor never again occur in gross forms and even subtly only occasionally.
In the eighth stage the elephant has turned completely white. He follows behind the man for the mind is now fully obedient. Nonetheless, some energy is still required in order to sustain concentration.
In the ninth stage the meditator sits in meditation and the elephant sleeps at his feet. The mind can now indulge in effortless concentration for long periods of time, even days, weeks or months.
These are the nine stages of the development of shi-nä. The tenth stage is the attainment of real shi-nä represented by the meditator calmly riding on the elephant's back.
Beyond this is an eleventh stage, in which the meditator is depicted as riding on the elephant, who is now walking in a different direction. The meditator holds a flaming sword. He has now entered into a new kind of meditation called vipasyana, or higher insight: (Tibetan: Lhag-mthong). This meditation is symbolized by his flaming sword, the sharp and penetrative implement that cuts through to realization of Voidness.
At various points in the diagram there is a fire. This fire represents the effort necessary to the practice of shi-nä. Each time the fire appears it is smaller than the previous time. Eventually it disappears. At each successive stage of development less energy is needed to sustain concentration and eventually no effort is required. The fire reappears at the eleventh stage, where the meditator has taken up meditation on voidness.
Also on the diagram are the images of food, cloth, musical instruments, perfume and a mirror. They symbolize the five sources of mental agitation, i.e. the five sensual objects: those of taste, touch, sound, smell and sight, respectively.
Geshe Rabten in The Perfection of Concentration